Holy Concentration vs Healing Prayers

I got a lot of comments, on and offline, that boiled down to: “Dude, you gotta have Holy Concentration, it rocks.” A common suggestion was dropping Healing Prayers – not everyone made this suggestion, but more than two (on and off). I decided to do a head to head comparison, drilling down into the details, as a topic. I’m going to warn you up front that in the end the answer is inconclusive — it literally depends on your playstyle as to which is better. If you want definitive… go somewhere else. On with the show.
Up front we’ve got hard numbers. Healing Prayers 2/2 reduces the mana cost of the two prayers – mending (PoM) and healing (PoH) – by 20%. Holy Concentration 3/3 gives you a restricted 6% chance of a limited clearcast — 6% of the GH, BH and FH casts will allow you to cast a free GH, BH or FH. Notice the very first assumption — two talent points vs three. A quite legitimate argument could be made that “fair” comparisons should use 2/3 for HC — a 4% chance. I’m not going to do so as I’m comparing maxed talent in both cases (another version of “fair”), but now you know you can make HC look worse at this point by being “fair”.

An HC proc CAN (we’ll return to that) give you up to 825 “free” mana — assuming you use max-rank GH AND you did not pick up the talent that reduced it’s cost by 15%. Applying the 15% reduction the max-rank GH cost 701 mana.

The HP saves 79 mana per PoM and 245 per PoH.

HC at 6% will proc about 1 out of every 16 casts. Perusing several battles on WowWebStats, I see that essentially every boss battle – regardless of actual spell patterns – has at least 15 of these procable casts. So we’ll take a working (simple) assumption as given — HC will proc once per boss battle.

To balance the mana saving on the first pass, I have to cast 9 PoMs or 3 PoHs to save the same amount of mana. ASSUMING — and this is critical — that I cast GH off the HC proc. Oh, and assuming that it didn’t proc on the last necessary heal of the battle.

Last necessary heal (wasted proc) means I have to reduce the mana savings by about 6%. On the other hand, the spell cast on proc is fully controllable, and I can certainly wait for GH to be necessary (especially since the cast won’t reset the 5sr clock). So let’s see where we are, now.

The proc saves … let’s round it to 660 mana. That’s a little better than 8 PoMs, but three PoHs will be better.

Back to sampling WWS. Where it’s used, it ranges from 4 to 12 uses in pre-heroic/Kara boss battles. The impression I get is that it’s used about 6 times each. 6 uses is about 480 mana which is less than the ~660 HoC saves

Same sampling, PoH gets used a minimum of four times if it’s used at all. (Surprising, and something else for me to re-examine.) Three PoHs save more mana than the HoC, so purely in terms of mana saved, PoH users are better off with the HP. Note for combinations that three PoM are roughly equal to one PoH for mana saved — and PoH users do use PoM frequently. (The reverse is not as common.)

But wait, there’s more. That’s because the HC proc makes the spell exempt from triggering the 5SR. We already decided we’ll use the proc for a GH — at worst, 2.5 seconds. And we’ll wait a bit more before using it. Quite simply, barring bad luck and bad timing we are going to get a MINIMUM of one tick of the waltz. More likely, we’re going to get three “free” ticks. At 200 spirit (an easy level for a priest) that’s 50 mana per tick for 150 mana. Two more PoM, and given the ‘leftover’ enough to balance one more PoH.

Which means that – provided you’re good at the dance, and depending on the situation and some luck, and YOUR PLAYSTYLE…. One will do you better than the other, by a little bit. (grin – told you it was inconclusive).

If you use the prayers heavily – to include PoH – then the Healing Prayers is probably your better choice. If you are a careful watcher of your procs so you don’t waste the clearcast, and you don’t particularly use PoH much at all, then HC is a clear winner. If you tend to miss procs (so you often ‘waste’ it on an FH) but don’t use PoH much at all, it’s going to be pretty close to tied.

Your playstyle, your taste, your choice. Think about it, and then have fun.

So, I think you’re vastly underestimating how often it’s likely to proc, although this obviously depends on your casting patterns (as you state). I basically expect it to go off once every 3 minutes, which is another reason why it works out to chain it with inner focus (usually) to get even more out-of-5-second-rule regen.

Um, Tanilin? at 6%, you should have had 5 to 6 procs on Hydross. You did get above average with almost 24% on Lurker and 8% on Morogrim.

Your other priest came close to being near the 6% for Hydross and Lurker, and was under on Morogrim.

But you’re looking at the wrong point. The essence was that on average over 16 GH/BH/FH casts you’ll get one proc, and most boss battles take long enough that you’ll get at least 16 casts of the appropriate type, and so will get at least one proc.

And so, over the same time period, a prayer-use player needs to do the example numbers of prayers to get a roughly equivalent return on mana.

It’s not how many procs did you get in a fight, it’s whether the fights are long enough to expect a proc. And the answer is yes.

About…

I've experience with many priests of many races and specs on several servers. The more I play, the more I realize how much I do not yet know. This is a share of some of what I have learned.
My main these days is Zingiber on the Undermine server.